title: Drugs and herbs given to prevent hepatotoxicity of tuberculosis therapy: systematic review of ingredients and evaluation studies.
abstract: BACKGROUND
  Drugs to protect the liver are frequently prescribed in some countries as part of treatment for tuberculosis. The biological rationale is not clear, they are expensive and may do harm. We conducted a systematic review to a) describe the ingredients of "liver protection drugs"; and b) compare the evidence base for the policy against international standards.
  
  
  METHODS
  We searched international medical databases (MEDLINE, EMBASE, LILACS, CINAHL, Cochrane Central Register of Controlled Trials, and the specialised register of the Cochrane Infectious Diseases Group) and Chinese language databases (CNKI, VIP and WanFang) to April 2007. Our inclusion criteria were research papers that reported evaluating any liver protection drug or drugs for preventing liver damage in people taking anti-tuberculosis treatment. Two authors independently categorised and extracted data, and appraised the stated methods of evaluating their effectiveness.
  
  
  RESULTS
  Eighty five research articles met our inclusion criteria, carried out in China (77), India (2), Russia (4), Ukraine (2). These articles evaluated 30 distinct types of liver protection compounds categorised as herbal preparations, manufactured herbal products, combinations of vitamins and other non-herbal substances and manufactured pharmaceutical preparations. Critical appraisal of these articles showed that all were small, poorly conducted studies, measuring intermediate outcomes. Four trials that were described as randomised controlled trials were small, had short follow up, and did not meet international standards.
  
  
  CONCLUSIONS
  There is no reliable evidence to support prescription of drugs or herbs to prevent liver damage in people on tuberculosis treatment.
authors.affiliation: School of Public Health, Chongqing Medical University, No,1 Yixueyuan Road, Chongqing, PR China. liuqin81622@163.com
authors.forename: Qin
authors.initials: Q
authors.lastname: Liu
authors.forename: Paul
authors.initials: P
authors.lastname: Garner
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.forename: Binghua
authors.initials: B
authors.lastname: Huang
authors.forename: Helen
authors.initials: H
authors.lastname: Smith
mesh_terms: D000995:Antitubercular Agents / Q000009:adverse effects*; D000075202:Contraindications; D064420:Drug-Related Side Effects and Adverse Reactions / Q000517:prevention & control*; D006801:Humans; D007668:Kidney / Q000187:drug effects*; D010946:Plants, Medicinal / Q000009:adverse effects*; D014376:Tuberculosis / Q000188:drug therapy*
chemical_list: D000995:Antitubercular Agents